nixpkgs-suyu/modules/programs/bash/bash.nix
Eelco Dolstra 24a44c98d2 bash: Disable hashing of command lookups in interactive shells
This just confuses people when (say) using multiple profiles.
Performance benefits for interactive shells are likely to be very
small anyway.
2013-07-31 14:55:24 +02:00

156 lines
4.2 KiB
Nix

# This module defines global configuration for the Bash shell, in
# particular /etc/bashrc and /etc/profile.
{ config, pkgs, ... }:
with pkgs.lib;
let
cfg = config.environment;
initBashCompletion = optionalString cfg.enableBashCompletion ''
# Check whether we're running a version of Bash that has support for
# programmable completion. If we do, enable all modules installed in
# the system (and user profile).
if shopt -q progcomp &>/dev/null; then
. "${pkgs.bashCompletion}/etc/profile.d/bash_completion.sh"
nullglobStatus=$(shopt -p nullglob)
shopt -s nullglob
for p in $NIX_PROFILES; do
for m in "$p/etc/bash_completion.d/"* "$p/share/bash-completion/completions/"*; do
. $m
done
done
eval "$nullglobStatus"
unset nullglobStatus p m
fi
'';
shellAliases = concatStringsSep "\n" (
mapAttrsFlatten (k: v: "alias ${k}='${v}'") cfg.shellAliases
);
options = {
environment.promptInit = mkOption {
default = ''
# Provide a nice prompt.
PROMPT_COLOR="1;31m"
let $UID && PROMPT_COLOR="1;32m"
PS1="\n\[\033[$PROMPT_COLOR\][\u@\h:\w]\\$\[\033[0m\] "
if test "$TERM" = "xterm"; then
PS1="\[\033]2;\h:\u:\w\007\]$PS1"
fi
'';
description = ''
Shell script code used to initialise the shell prompt.
'';
type = with pkgs.lib.types; string;
};
environment.shellInit = mkOption {
default = "";
example = ''export PATH=/godi/bin/:$PATH'';
description = ''
Shell script code called during login shell initialisation.
'';
type = with pkgs.lib.types; string;
};
environment.interactiveShellInit = mkOption {
default = "";
example = ''export PATH=/godi/bin/:$PATH'';
description = ''
Shell script code called during interactive shell initialisation.
'';
type = with pkgs.lib.types; string;
};
environment.enableBashCompletion = mkOption {
default = false;
description = "Enable Bash completion for all interactive shells.";
type = with pkgs.lib.types; bool;
};
environment.binsh = mkOption {
default = "${config.system.build.binsh}/bin/sh";
example = "\${pkgs.dash}/bin/dash";
type = with pkgs.lib.types; path;
description = ''
Select the shell executable that is linked system-wide to
<literal>/bin/sh</literal>. Please note that NixOS assumes all
over the place that shell to be Bash, so override the default
setting only if you know exactly what you're doing.
'';
};
};
in
{
require = [options];
environment.etc =
[ { # Script executed when the shell starts as a login shell.
source = pkgs.substituteAll {
src = ./profile.sh;
wrapperDir = config.security.wrapperDir;
inherit (cfg) shellInit;
};
target = "profile";
}
{ # /etc/bashrc: executed every time an interactive bash
# starts. Sources /etc/profile to ensure that the system
# environment is configured properly.
source = pkgs.substituteAll {
src = ./bashrc.sh;
inherit (cfg) interactiveShellInit;
};
target = "bashrc";
}
{ # Configuration for readline in bash.
source = ./inputrc;
target = "inputrc";
}
];
environment.shellAliases =
{ ls = "ls --color=tty";
ll = "ls -l";
l = "ls -alh";
which = "type -P";
};
environment.interactiveShellInit =
''
# Check the window size after every command.
shopt -s checkwinsize
${cfg.promptInit}
${initBashCompletion}
${shellAliases}
# Disable hashing (i.e. caching) of command lookups.
set +h
'';
system.build.binsh = pkgs.bashInteractive;
system.activationScripts.binsh = stringAfter [ "stdio" ]
''
# Create the required /bin/sh symlink; otherwise lots of things
# (notably the system() function) won't work.
mkdir -m 0755 -p /bin
ln -sfn "${cfg.binsh}" /bin/.sh.tmp
mv /bin/.sh.tmp /bin/sh # atomically replace /bin/sh
'';
environment.pathsToLink = optionals cfg.enableBashCompletion [
"/etc/bash_completion.d"
"/share/bash-completion"
];
}